substitute

Adjective

• artificial and inferior
  • ersatz coffee
    
  • substitute coffee
    

• serving or used in place of another
  • an alternative plan
    

• capable of substituting in any of several positions on a team
  • a utility infielder
    

Noun

• someone who takes the place of another (as when things get dangerous or difficult)
  • the star had a stand-in for dangerous scenes
    
  • we need extra employees for summer fill-ins
    

• an athlete who plays only when a starter on the team is replaced

• a person or thing that takes or can take the place of another

Verb

• act as a substitute
  • She stood in for the soprano who suffered from a cold
    

• be a substitute
  • The young teacher had to substitute for the sick colleague
    
  • The skim milk substitutes for cream--we are on a strict diet
    

• put in the place of another; switch seemingly equivalent items
  • the con artist replaced the original with a fake Rembrandt
    
  • substitute regular milk with fat-free milk
    
  • synonyms can be interchanged without a changing the context's meaning
    

Related words

• Synonyms: 
  ersatz , alternate , alternative , utility(a) , substitute(a) , stand-in , relief , reliever , backup , backup man , fill-in , reserve , second-stringer , replacement , deputize , deputise , step in , sub , stand in , fill in , replace , interchange , exchange